Not wanting to join the titanum fray or add fuel to the fire (I am also from
"Down Under", well, almost - South Africa), but only to disseminate
statistics...

The largest titanum in "my" titanum forest (18 plants) from Jim Symons'
seed sports a petiole length of 1.6 metres (63 inches I think) up to the
point of "trifurcation" and a leaf diameter of similar dimensions, i.e. a
great plant! I am too scared to exhume a tuber, so no statistics there.

I will certainly be looking out for developing inflorescences the next time
they go dormant!